Method of and machine for folding sheet material



I Sept. 23, 1930. P. R. GLASS METHOD OF AND MACHINE FOR FOLDING SHEET MATERIAL "Filed Aug. 9, 1923 2 Sheets-Sheet 1 Se t. 23, 1930. P. R. GLASS 1,776,425

METHOD OF AND MACHINE FOR FOLDING SHEET MATERIAL Filed Aug. 9, 1922' v 2 Sheets-Sheet 2 Patented Sept. 23, 1930 UNITED STATES PATENT OFFICE PERLEY R. GLASS, 0F WAYLAND, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY,

A CORPORATION OF NEW JERSEY OF AND MACHINE FOR FOLDING SHEET MATERIAL Application filed August a, 1923. Serial No. 656,557.

This invention relates to methods of and ing of the margins of the covers of book cases theboard or boards upon which the covers are mounted.

In the manufacture of memorandum books,

pocket-books and similar articles it iscustomaryto attach to the board or boards by means of paste a cover of leather or imitation leather the margins of which extend beyond-the edges of the boards and then to apply paste to these margins and fold them over upon the adjacent margins of the boards. The corners of the finished case may be rounded or square; and the manner in which they are cut and folded differs according to whether theyare to be the one or the other. Hitherto, the folding operations have been largely carried out by hand; and the general object of the present invention is to provide a machine which shall do away ith hand folding.

According to the present invention. the machine is provided With mechanism for folding the m argins along straight edges irrespective of the shape of the corners, and with two conveniently located mechanisms for folding the corners, one mechanism being adapted to fold rounded and the other square corners. All that is required of the operator is'to present the various localities of the work to the proper mechanisms, the necessity which formerly obtained for skill on the part of the operator being largely obviated, and the time consumed greatly lessened.

In the manufacture of book cases having rounded corners, it is customary to prepare the boards with corners of the desired curvature and to prepare the covers with similarly rounded corners; and then, when the sev-.

eral corners of the cover are folded, to plait the margin of the'cover at the localities in which it is folded over the rounded corners of the boards. According to one feature of the present invention there is provided an edge guide having two faces arranged to include between them an angle and a folder having two faces arranged to include between them a smaller angle. In the illustrative machine the-angle included between the faces of the edge guide is a right angle, since'practically all book covers have four edges arranged in the form of a rectangle; and the faces of the folder include between them an acute'angle.

The work, which consists of the usual boards and cover is presentedcorner-foremost to the guide in such manner that the margin of the cover atand achacent to the corner is ben'tup- 'wardly bytlie guide, and then the folder is caused to move over the guide. Because the faces of the folder include between them an acute angle, the folding of the corner takes place progressively beginning at two points spaced from the apex of the corner andendwiping of the margin of the cover over the board tends to the formation of regular plaits of substantially equal SlZG, I In order however to ens'u're a more precisely regular formationof plaits as well as to aid in the proper presentation of the work to the guide, there may be provided a tool'which cooperates with the margin during the folding operation so as to aid in plaiting the corner of the cover at the proper localities.

In the manufacture of books having'square "corners it is customary to use boards having square corners, and covers the corners of 'WlHCh have been cut off on an angle of about 135 degrees to the adjacent edges, the cutting- 'OfI being done to avoid objectionable thickness and unevenness in the finished folded corners. 'lVith' the boards and covers shaped as indicated above and pasted together in the 'usual manner, it is desirable, in order to secure a smoothly folded corner, first to fold the margin of the cover along one edge over the board, then to'form a plait in a portion of the margin of the cover adjacent to the corner and finally to fold the margin of the'cover along the other edge over the board. According to another feature of the invention means are provided for forming bills-1313,11). In the illustrative machine this means is associated ing at the apex, This progressive folding or I with and includes part of the mechanism for folding the straight edges. The edge guide is pro *ided with a short face parallel to but offset from the long or main face so to form a shoulder at their adjacent ends. After the entire margin along one edge of the cover has been folded by presenting it to the main face of the edge guide and causing a co-operating folder to operate, the folded'margin adjacent tothe corner is presented again, but'this time to the offset face of the guide and held close up to the shoulder while the machine is operated once more. The presentation causes the formation of a pucherat the desired locality; and this pucker is pressed into a plait by the folder. The work is then turned 90 degrees and presented a third time to the main face of the edge guide, as in the first instance, to fold the margin at the adjacent side of the corner.

Considered in another aspect the invention provides a novel method of folding book covers, particularly those having rounded corners.

Referring now to the accompanying drawings,

Fig. 1 is a perspective of amachine in which the present invention is embodied and by the use of which the method may be practised,

Fig. 2 is a section on the line 2.2 of Fig. 1,

Fig. 3 is a perspective of the two folders, the corner folder and the straight folder,

Fi i is a perspective of the plaiting tool,

Figs. 5, 6 and 7 are details in section showing different steps in the folding of a rounded corner,

Figs. 8 and 9 are perspectives respectively of a rounded corner before and after the folding operation has been carried out,

Fig. 10 is a, perspective showing the shapes of the boards and cover when square corners are to be produced,

Figs. 11, 12, 13 and let are perspectives showing steps in the folding of a square corner.

Referring first to Figures 8 and '9, it will be noted that the work comprises the board 100', which may be of cardboard, pasteboard, 7

heavy paper or any suitablematerial, and the cover 200 which may be of any flexible material and is commonly of leather or imitation leather. It will be understood that there are usually two boards placed with respect to the cover as shown in Figure 10 presently to he described. There are thus four straight edges and four corners to be folded. Where rounded corners are desired, the boards are cut with rounded corners and the cover with similarly rounded corners or with partially cut-off square corners,-the margin of the cover projecting, as shown, beyond the edges of the boards; and when the corner of such a cover is folded over the corner of such aboard, the

' corner of the cover should'loe plaited after the manner indicated in Figure 9. lVith the machine of the present invention the work is first presented to corner-folding mechanism and then to mechanism for folding the straight edges, although, .as will presently two faces which include between them an angle equal to the angle included between the twostraightedges of the board 100' which are adj acent to a rounded corner, and a folder 19 having two faces which include between them a smaller angle. The angularly arranged faces of the edge guide 17 are connected by a face which is curved. to correspond to the curve of the rounded corner of the board 100; and the adjacent edge of tie support 15 is curved in the same manner at'the junction of its two angularly arranged faces, while the curve at the junction of the two angularly arranged faces of the folder 19 is a little more abrupt. Inthe operation of the machine, the work, in the condition shown in Figure 8 is placed upon the support l5'with the rounded corner of the board pushed as far as possible toward the edge is 17 so that the projecting margin of the cover 200 is bent upwardly and extends above the guide. A treadle is then depressed, whereupon the folder 19 moves toward the operator to fold the margin of the cover over upon the board, after which the supportinoves upwardly to press the fold thus formed, it being understood that paste has previously been applied to the projecting margin .of the cover tocause it to adhere to the board. Inasmuch as the angle included between the faces ofthe folder is smaller than that included between the faces of the edge guide, the folding operation takes place progressively beginning at two points spaced from the apex of the corner. In order to pucker and plait the corner regularly so that there may be no objectionable bunches in the finished corner, as well as to facilitate the proper presentation of the worl: to the edge guide, there is provided a combined work presser and plaiting tool in the form of a rod 21 havingadjustably fastened to its lower end a pla-iti-ng-tool- 23 comprising plurality of spaced ribs or corrugations ar ranged to diverge slightly. Before the folder l9 begins its folding movement, the rod -21 is first brought down to press the work firmly against the support 15, as shown in Figure 5, and is then raised slightly. It is so mounted that it can he swung yieldingly to the left,

as viewed in Figure 6, by the folder during the folding movementof that member. Dull- 'ing the folding movement, therefore, it drags over the inner face of the margin of the cover and tends to crease the margin and thereby to cause the formation of properly spaced puckers which are, by the subsequent upward movement of the support 15, pressed into plaits. It will be noted that the plaiting tool is located in the path of movement of the folder, that a portion of it extends above the folder and overhangs the folder during, the folding operation, and that the tool is yieldingly pressed against the inner face of the margin of the work so that the margin is frictionally gripped between the opposed faces of the folder and the tool during said folding operation.

7 If the piece of work is small enough the folding of the four corners in the manner described will effect the folding of the four straight edges as well, since portions of theseedges are folded when the corners are folded. For the larger covers, however, it is preferable to provide additional mechanism for folding the straight edges. To this end there is provided a work support 27, an edge guide to conform to the contour of the edges of the cover which extend between the corners (in. the illustrative machine a straight edge guide 29) and a folder 31. The general mode of operation of these parts is the same as that of the corner-folding parts which has been described above. The straight edge of a board is pushed as far as possible toward the straight guide 29 so that the projecting margin of the cover extends upwardly, the folder moves over the guide to form the fold, and then the'support risesto pressthe fold. It will benoted that the straight-edge folding mechanism is locatedat a level below 'that'of the round corner folding mechanism.

lVith this brief description of the mode of operation ofthe machine, a detailed description will now be given. The two work supports 15 and 27 are fastened respectively by screws. two of which are shown at 33, 35, to a cross-head 37 which is vertically slidable in suitable 'guideways formed in the forward part of the frame 39 of the machine.

Extending rearwardly from this cross-head is a lug 41 to which 15 pivoted the lower end of a link 43 the upper end of which is pivoted to the forward end of a second link 45, the

rear end of said link 45 being pivoted on a stationary rod 47. Also pivoted on the rod 47, or. rather upon a small eccentric formed integral with it, as shown in Figure 2, is the hub of a lever 4-9 having at its outer end a forkto receive a cam 51 on the driving shaft 53. 'Integral with the hub of the lever are two arms 55, 57 which extend respectively above and beneath the link 45. The lower arm 57 has formed in it a socket to receive a spring 59 which rests at its lower end upon a tension-varying screw Gland bears with its upper end against the under side of a collar which isfastto or integral with a vertical rod 63, said rod bearing against the under side of the link 45. Threaded through the upper '45 and with it thecross-head 37 and the work j'supports l5 and It should be noted that the raising of the work-supports takes place yieldingly through the spring 59 so that, during the pressing of a fold, there will be no danger of breaking any part; and, at the same time, foldsrwhich differ somewhat in thickness may be pressed. If folds which differ considerably in thickness are to be pressed, the rod d7 may be turned to bring the eccentric upon it with a different angular position. In order to facilitate this adjustment there is fast to one end of this rod a handle'69 having integral with it a slotted segment '71 through the slot of which passes the stem of a cap screw 73. This screw is threaded into the frame of the machine and carries between its head and the outer face of the segment 71a washerand a coiled spring. When the, cap screw 1s loosened, the handle 69 may be turned; at other times 1t is held 'are two lugs 75 which rece'ive'between them a roll 7'7 carried at the upper end of an arm 79 which is pivoted at 81 to the frame of the machine.

Mounted on the arm 7 9 intermediate its ends is a cam roll 83 which runs on a cam 85 mounted on the driving shaft 53 at one side of the cam 51. A spring-pressed plunger 8?, having at its outer end an anti-frietion roll 89, urges the arm 79 to the right, as viewed in Fig. 2, so as to ho] d the cam roll 83 in contact with the cam 85. The folder 19 is slidable in suitable horizontal guideways and prevent lateral movement; and when a revolution is imparted to the driving shaft 53, the folder, owing to the shape of the cam 85, is first moved forward to form the fold. then held stationary while the fold is pressed, and then returned to initial position. The straightedged folder 31 is also mounted in suitable guideways in the frame of the machine and partakes of the movements of the corner-folder 19. It is attached to the folder 19 (see Fig. 3) by studs 91 which extend up wardly into holes 93 in the folder 19 and downwardly into holes 95 in rearward extensions formed on the folder 31. "The mechanisms for operating the folders and work supportsare constructed and arranged first to cause the folders to move forward (to the left iewed in Fig. 2) and come to rest above the supports, then to cause the supports to be raised, and then to return the folders and supports to the positions shown in F 2 ready for the presentation to the machine of another side or corner of the work. The rotation of the shaft 53 is caused by means of a treadle-controlled one-revolution clutch which will not be described, since the details of its construction form no part of the present invention and since any suitable means for imparting at will one revolution to the shaft 53 may be employed.

The presser rod 21, which carries the plaiting tool 23, is held in a block 97 which is pivoted about a small red 99 held in the arms of a yoke 98 the stem of which is adjustably held in a carrier in the form of a split sleeve 101 by a pinch-screwlOB. The block 07, as best shown in Fig. 2, has an upper arm eX- tending over the yoke 98 and a lower arm extending beneath the yoke. A springpressed plunger 105 carried by the upper arm and a. stop-screw 107 carried by the lower arm tend at all times to hold the block 97, and with it the presser-rod 21 and plaiting tool 23, in the position with respect to the pivot 99 shown in Fig. 2. It should be noted, however, that the plait' 'tool may be pushed to the left at any time; and this is what occurs, as has been explained, during the folding operation.

The carrier 101 has integral with it a hub 109 loosely mounted on a rod 111 carried by upstandin lugs which project from the top plate of the machine. Also integral with the carrier 101 is a member 113 having a bore to receive aheaded plunger 115. The head of the plunger bears upon a stationary hardened plate .117: its stem, which extends up th ough the bore in the member 113, has check nuts 119 threaded upon its upper end; and a coiled spring 121 tends at all times to cause the plunger to urge the carrier 101 upwardly about the axis of the rod 111, such upward movement being; limited by stop 123 carried by a tail 125 formed on the hub 109. Extending from the hub 109 and connected with the carrier 101 by a web 127 is an arm 129 to which is pivoted the upper end of a treadle-rod 131 so that. by exerting; a downward pull upon the rod, the presser 21 and plaiting tool 23 may be brought down upon the work into the position shown in Fig. hen a. piece of work is presented to the corner-folding mechanism it is desirable that the presser 21 should be brought down upon the board 100 so as to press the work firmly down upon the work support and should then be released by being raised slightly so as to permit the plaiting; tool to be swung about its pivot 99 during the fold ing operation.

This could, ofcourse, be accomplished by first depressing the treadle which is attached to the treadle rod 131 and then allowingthe treadle to rise slightly and holding it in that position during the folding operation. 111 the present machine, however, depression and release of the treadle is all. that is necessary first to bring the ,presser 21 down into the position shown in Fig. 5, then to raise it slightly so as to permit it to be pushed to the left during; the folding operation, and finally to return it to the position shown in Fig. 2. To this enda lug which is integral with the web 127 has at its outer end a slot 133 through which extends the stem of a hardened. block 135. A washer 137 and nuts 189 provide means for adjusting the stem to and holding it in any desired position in the slot. This block is normally in raised position and below it is a catch 141 underneath which it engages when the treadle rod 131 is pulled down. The catch-is carried at the upper end of a smooth stem 143 which fits loosely in a vertical socket in a lever 145, said lever aeing pivoted at 147 to the frame of the machine. A spring 140 tends at all times to urge the lever toswing in a clockwise direction. It is held normally in the position shown in Fig. 2 by reason of the fact that an inclined face on a lug which extends upwardly from the catch 141 is in contact with the block 135. The vertical position of the catch 141 with respect to the lever 145 may be varied by turning a thumb-screw 151, which is threaded into the top of the lever and has two collars one above and the other below a forked extension on the catch. The catch 141 is adjusted into such a vertical position that, when the treadle h as been depreseed sufliciently to bring the rod 21 down into position to press the work firmly upon the support 15, as shown in Fig. 5, the upper face of the block will be slightly below the ope-rative under face of the catch so that, when the treadle is released. the spring 121 will raise the block slightly until it engages the catch, this upward movement, serving to release the pressure of the rod 21 on the work, whereupon the rod may swing to the left,

as shown in Fig. 6. during the folding operation. At the completion of the folding operation, or just before the completion of that operation, the upper portion of the lever 145 is swung to the left, as viewed in Fig. 2, to release the block 141 and permit the carrier 101 to rise, this swinging of the lever being brought about by contact with it of a screw 153 which is threaded through a boss carried by the folder 19 and held in adjusted position by a lock-nut. 7

Although not herein shown, the present machine is equipped witha treadle of the toeand-heel type, the heel end being connected with the treadle rod 131 and the toe end with the trcadle rod (not shown) which throws in m ss the one-revolution clutch. Assuming now that the piece of work comprises four straight edges and four rounded corners, the operation of the machine is as follows: A corner in the condition shown in Fig. 8, to the projecting margin of the cover 200 of which paste has been applied, is presented to the corner-folding mechanism and then first the heel end and then the toe end of the treadle is depressed. Depression of the heel end brings the presser 21 and plaiting tool 23 into the position shown in Fig. 5 to press the-work firmly against the work support, the block 135 being then slightly below the catch 14-1. When the'toeend of the treadle is depressed, the heel end is released, with the result that the presser 21 and plaiting tool 23 rise slightly so as to befrce to swing. The folder 19 now moves to the left beneath the plaiting tool 23, and folds the margin of the cover 200 over the boardlOO in the man ner shown in Fig. 6. During this folding movement the plaiting tool, under the in fluence of. the spring-pressed plunger 105, is caused to drag over the inner face of the corner of the margin; and this dragging, in cooperation with the operation of the folder, forms evenly spaced puckers in the margin. At the same time the margin of the cover is gripped frictionally between the tool or member 23 and the folder 19 and pulled tightly about the edge of the board. Just before or at the moment the folder has completed its forward movement, the screw 153 strikes the lever 1 15 and releases the block 135, whereupon the plaiting tool rises to its normal in operative position shown in Fig. 2. After the folder has completed the formation of the fold, it pauses while the work support 15 is moved upwardly to press the fold, as shown in Fig. 7. Thereafter the work support and the folder are returned to their normal, inoperative position, and the machine comes to rest. The remaining three corners are then folded in the same manner. If the pieceof work is sufliciently small, or if the corner folding mechanism 18 sufficiently large, the foldlng of the corners may sufiice also to fold the four straight portionsf Otherwise the four straight portions are presented in succession to the straight-edge folding mechanism comprising the work support 27, edge guide 29 and folder 31, which operates eX actlv like the corner folding mechanismexcept that no plaiting tool is employed.

The paste used in this work tends to collect and harden on the under side of the folders 19 and 31 and to interfere with the proper operation of the machine. In order to overcome thisdifiiculty a piece of moist, absorbent material 155, such as felt, is set in the edge guide 29 in position to wipe across the under face of the folder 31; and a similar piece 157 is similarly located with respect to the corner folder 19. By providing means for moistening the under faces of the folders, the collection and hardening of paste upon them is obviated.

When square corners are to be produced it is customary to prepare the work as shown in Fig. 10 in which the boards 300 have the desired square corners while the corners of the covers have been out off as shown to remove surplus material which would otherwise cause an undesirable bunch in the folded corners. In folding such a piece of work it is desirable first to fold the straight portion on one side of a corner, as shown in Fig. 11, and then to form a plait at or near the junction of the two margins prior to folding the straight portion whichis located at the other side of the corner. In the present machine the straight edge-guide 29 is provided with two faces 157, 159 parallel to but ofi'set from each other .so that there is formed between their adjacent ends a .shoulder 161. In folding a.

piece of work such as that shown in F ig. 10, the whole of one margin is first folded by presenting the work in the manner which has been described tothe face 157 of the edge guide and throwing in the one-revolution clutch. The work is then in the condition shown in Fig. 11. The work adjacent to the corner is then presented to the face 159 of the edge guide in' the manner shown in Figs. 12 and 13. The result of this presentation is to crumple the cover more or less adjacent to the corner and to form a pucker 163. One end of the folder 31 is alined with the shoul der 161; and when the one-revolution clutch is thrown in the pucker is pressed fiat to form a sort of plait. The work is next turned ninety. degrees, the margin on the other side of the corner presented to the straight face 157, and the one-revolution clutch thrown in to produce the result shown in Fig. 14. The operator then proceeds to pucker and plait the next corner, and so on until the entire margin of the cover is folded. In order to provide for right-hand and left-hand corners, with reference to the work when it is in the condition shown in Fig. 11, the edge guide 29 (see Fig. l) is provided with two face-s 159 which are offset from the face 157 and with two shoulders the faces of which are respectively alined, or substantially so, with the ends of the folder.

Throughoutthe specification, the edges'of the cover which extend from one corner to another have, for convenience, been referred to as straight edges, although whether they are in every case straight is immaterial.

Having described my invention, what I- claim as new and desire to secure by Letters Patent of the United States is 1. A machine for folding the covers of book cases which have straight edges and round nism located at a lower level, the two mechanisms being located and arranged to permit a straight edge and a round corner of a book case to be presented in Succession to the mech anisms by an operator whose position remains unchanged.

2. A machine for folding the covers of book cases which have straight edges and round corners having, in combination, a cross-head, means for reciprocating the crosshead, two work supports carriedby the crosshead, an edge guide and a folder each having a single straight face associated with one work support, an edge guide and a folder each having two faces arranged at an angle to each other and associated with the other work support, the construction and arrangement being such that a straight edge and a round corner of a. book case .may be placed in succession upon the work supports by an operator whose position remains unchanged, and means for reciprocating the folders.

3. A machine of the class described having, in combination, an edge guide having a pair of faces arranged to include an angle between them, a folder having a pair of faces arranged to include between them a smaller angle, and

means for causing relative reciprocation be faces arranged to includebetween them a smaller angle, and means for causing relative movement between the work support and the folder first in a direction to cause the folder to overhang the support and then in another direction to cause approach of the folder and support, said folder being held from lateral oscillation.

5. A machine for folding the cover of a book at a corner thereof having, in combination, an edge guide having two faces arrangedto include between them an angle sub stantially the same as that which isto be included between the two folded edges of the cover, a folder having two faces which include between them a smaller angle, means for producing relative movement between the guide and folder to form the fold, and means for pressing the fold, said folder being held from lateral oscillation.

6. A. machine for folding the cover of a bookat a corner-thereof having, in combination, an edge guide having two faces arranged to include between them an angle substantially the same'as that which is to be included betweenthe folded edges of the cover, means for folding the corner progressively beginning simultaneously at two points spaced from the corner, a tool adapted to act upon the corner in cooperation with the folding means to facilitate the formation of plaits, and means for pressing the fold.

7. A machine for folding the cover of a book at a corner thereof having, in combination, an edge guide having two faces arranged to include between them an angle substantially the same as that which is to be included between the folded edges of the cover, means for folding the margin at the corner progressively beginning at two points spaced from the corner, a member adapted to cooperate with the folder in the formation of plaits, and means for holding the member, during the folding operation, against the inner face of the margin in a locality opposite to that engaged by the folder.

8. A. machine for folding the cover of a book at a corner thereof having, in combination, an edge guide having two faces arranged to include between them an angle substantially the same as that which is to be included between the folded edges of the cover, a folder having two faces which include between them a smaller angle, means for producing relative movement between the guide and folder for forming the fold, a plaiting tool adapted to act upon the corner during the folding operation, yielding means acting through the tool in opposition to the movement of the folder during the folding operation, and means for pressing the feld.

9. A machine for folding the corner of the cover of a book over the corner of the board to which the cover is attached having, in combination, a support for the work, an edge guide, a plaiting tool, a folder, means for causing the tool to press upon the board, means for moving the folder, and means coming into operation before the completion of the movement of the folder for raising the plaiting tool and holding it in position to drag over the inner face of the margin of the cover.

10. A machine for folding the cover of a book at a corner thereof having, in combination, a support for the work, a folder, means for operating the folder to form the fold, a combined work presser and plaiting tool, and means operating first to cause the combined member to force the work against the work support and then to release the member to permit the member to drag over the inner face of the margin of the cover during the operative movement of the folder.

11. A machine of the class described having, in combination, a support for the work, an edge guide having two faces one of which is offset with respect to the other to form a shoulder, a folder one end of which is substantially in register with the shoulder, and means for causing relative movement betweenv the folder and support first to bring the shoulder beneath the folder and then to cause movement of approach between the folder and the support. 7

12. A machine of the class described having, in combination, a support for the work, an edge guide having two faces one of which is offset with respect to the other to form a shoulder, a folder one end of whichis substantially in register with the shoulder, and

: means for operating the folder and the support. I

13. A machine of the class described having, in combination, a support for a piece of work comprising a rectangular backing of comparatively stiff material over one margin of which the margin of a flexible cover has been folded and over the adjacent mar gin of which the adjacent margin of the cover is to be folded having, in combination, an edge guide having an offset portion to whlch the work may be presented to pucker a vportion of the unfolded margin, and means for exerting pressure upon the puckered portion prior to folding the margin.

14. A machine for operating upon two margins of the cover of a book which lie at an angle to each other outside a sharp corner of the board to which the cover is attached having, in combination, means for folding one margin over the board, and means for thereafter puckering the cover adjacent the corner of the board preparatory to folding the remaining margin.

15. A machine for operating upon two margins of the cover of a book which lie at an angle to each otheroutside the edges of a sharp corner of the board to which the cover is attached having, in combination,

two faces one of which is offset with respect to the other to form a shoulder to which the partly folded margin of the cover may be presented in such manner as to form a puck er in the cover, a folder one end of which is substantially in register with the shoulder,

means for causing relative movement between the support and the folder in a direction to cause the folder to overhang the pucker, and means for causing furtherrelative movement between the same members in another direction to press the pucker into a plait. i e

v 17. A machine for operating upon two margins of the cover of a book which lie at an angle to each other outside the edges of the sharp corner of the board to which the cover is attached having, in combination, a support for the work, an edge guide having two faces one of which is offset with respect to the other to form a shoulder to which the partly folded margin of thecover may be presented in such manner as to form a pucker in the cover, a folder one end of which is substantially in register with the shoulder, means for moving the folder over the pucker, and means for causing relative movement of approach between the folder and the sup, port to pressthe-pucker.

18. A machine for operating upon two margins of the cover of a book which lie at an angle to each other outside'the edges of the sharp corner of the board to which the cover is attached, having, in combination, a support for the work, an edge guide having two faces one of which'is offset with respect to the other to form a shoulder to which the partly folded margin of the cover may be presented in such manner as to form a pucker in the cover, a folder one end of which is substantially in register with the shoulder, means for moving the folder over the pucker, and means for moving the support toward the folder to press the pucker.

1%). A machine for folding the margin of a piece of flexible material to which paste has been applied having, in combination, a support for the material, a folder movablein a path to bend the'margin of the material over the bodyportion thereof, and means 10-- cated in the path of movement of the folder for supplying moisture to a surface of said folder.

20. A machine for forming a fold in the margin of a piece of flexible material to which paste has been applied having, in combination, a support for the material, a. movable folder, a support for the folder and a piece of moist absorbent material mounted in the folder support and arranged to engage one face of. the folder.

21 Mechanism for folding the margin of a book-cover or similar article at a corner thereof having, in combination, an edge guide having divergent faces the curve at the junction of which corresponds to the curve desired on the finished corner of the cover, a folder havingv divergent faces, the curve at the junction of which is of smaller radius than that at the junction of the faces of the edge guide, a work support, and means for causing relative movement between the folder and the work support first in a direction to cause the folder to overhang the work support and then in a direction to cause approach of the folder and work support.

22. Mechanism for folding the margin of a book-cover or similar article having, in combination, an edge guide having an outline corresponding to the outline desired on the corner of the finished cover, a work support a portion of which has a similar outline, a folder having divergei'it faces, a tool adapted to cooperate with the folder to facilitate the formation of plaits said tool being normally raised above the work su'pport'suificiently to permit a book-cover to he presented beneath it, means for moving the tool down into the path of the folder, means for moving the folder over the edge guide first to force the inner face of the margin of the cover against the tool and then to bend the margin down over the body portion'ofthe cover, the inner face of the margin dra ing over the contacting face of the tool during this bending, and means for thereafter causing relative movement of approach between the support and the folder. I

23. hilechanism for folding the margin of a book-cover or similar article at a corner thereof havin in combination, an ecge guide having divergent faces joined by a curved face the curvature of which corresponds to the curve desired on the finished corner of the cover, a folder having divergent faces joined by a curved face, .he curve of which is of smaller radius than that of the edge guide, a work support shaped to extend into the space defined by the edge guide,a tool adapted to cooperate with the folder to facilitate the formation of plaits, said tool being normally raised above the work support sufficiently to permit the corner of a book-cover to be laid on the work support with the margin of the cover overlying the edge guide, means for moving the tool down into the path of the folder, means for movingthe folder over the edge guide, whereby the margin is first forced against the tool and then bent down over the body portion of the cover, and means for causing relative move ment of approach between the folder and the work support to press the bent over margin into place.

24. Mechanism for folding the margin at the corner of abook-cover or similar article having, in combination, a work support, an edge guide, a folder, means for moving the folder over the edge guide and the work support to form the fold, means for causing relative movement of approach between the folder and support to press the fold, a tool adapted to cooperate with the folder-to facilitate the formation of plaits, and means for continually urging the tool into the path of movement of the folder during the movement of the folder over the edge gage and work support.

A machine for folding the covers-of book cases which have straight edges and round corners, said machine having, in combination, corner folding mechanism including an edge guide having two faces arranged at an angle to each other and a folder also having two faces arranged at an angle to each other, straight edge folding mechanism including a straight-faced edge guide and a straight faced folder, said mechanisms being located and arranged to permit a straight edge and a corner of a book case to be presented in succession to the mechanisms by an operator whose position remains unchanged, and means for operating the mechanisms.

26. The method of folding book covers which comprises folding in succession two adjacent corners and then folding the margin which extends between them.

2?. A machine of the class described having, in combination, a support for the corner portion of a piece of sheet material, means forfolding the margin of said corner portion at a single operation, a co-operatiug tool adapted to facilitate the formation of evenly spaced plaits in the folded n'iargin, said tool being movably mounted in the path of movement of the folding means, and yielding means for causing the tool to oppose the mrw'ement of the folder during the folding operation. 7

A machine of the class described having, in con'ibination, a support for the corner portion of a piece of work, a folder movable to fold the margin of the cornerportioi'i at a single operation, a co-operating member for engaging'the inner face of the corner portion, and yielding means acting'in opposition to the folding movement of the folder for holding the member in contact with the inner face of the margin.

29. A machine of the class described having, in combination, a support for the corner portion of a piece of work, a folder movable to fold the margin of the corner port-ion at a single operation, a cooperating member for engaging the inner face of the corner portion, yielding means acting in opposition to the folding movement of the folder for holding the member in contact with the inner face of the margin, and means for pressing the fold.

30. A machine for folding the cover of a book at a corner thereof having, in combination, an edge guide having a curved portion the curvature of which corresponds to the desired curvature at the corner of the finished cover, a folder having a curved portion the curvature of which is'more abrupt han that of the corresponding portion of the ed guide, and means forproducing relative moven'ient between the folder and the edge guide to fold the corner of the cover.

31. A machine for foldingthe coverof a book at a corner'thereof having, in combination, an edge guide having a curved portion the curvature of which corresponds to the desired curvature at the corner of the finished cover, a folder having a curved portion the curvature of which is more abrupt than that of the corresponding portion of the edge guide, means for producing relative movement between the folder and the edge guide to fold the corner of the cover, and a member adapted to cooperate with the folder to facilitate the formation of the margin. V 1

32. A machine for folding the cover of a book at a corner thereof having, in combination, an edge guide having a curvedportion the curvature of which correspondsto the desired curvature at the cornerof the finished cover, a folder having a curved portion the curvature of which is more abrupt than that of the corresponding portion of the edge guide, means for producing relative movement between-the folder and the edge guide to, fold the corner of the cover, armember adapted to cooperate with the folder to facilitate the formation of evenly spaced plaits in the margin, and yielding means for urgingthe member toward the folder.

33. A machine for folding the margin of the cover of a book at a corner thereof havevenly spaced plaits in ing, in combination, a support for the work,

a folder, the operative edge of which comprises diverging faces, said folder being held from oscillation and adapted to fold themargin at the corner over thebody. portion of the work at a single operation, and a member located in the path of movement of the folder adapted to co-operate with the folder during the folding operation to facilitate the formation'of evenly spaced plaits.

34. A machine for folding. the margin of a piece of work at a round corner thereof in a single operation having, in combination, means for bending up the margin, a folder; havinga recess in its forward edge, a member adapted to cooperate with the recessed edge of the folder to facilitate the formation of evenly spaced plaits in themargin, said folder and member having opposed operative faces, and means for causing the margin to be grippedfrictionally between'said faces and, while so gripped, laid over upon the body portion of the work.

35. A machine for folding the margin of a piece of work at a round corner thereof having, in combination, a folder held from lateral oscillation movable over the bodyportion of the work, a member adapted to cooperate with the folder to facilitate the formation of plaits inthe margin of the work, and means for normally holding the member yieldingly adjacent to the corner. A

36. A machine for folding the'ma'rgin of'a piece of work at a round corner thereof having, in combination, a folder for engaging the outer face of the margin and bending the margin over the body portion of the work, a member adapted to cooperate with the folder to facilitate the formation of plaits, and means for causing the operative face of the member to pass progressively over the inner face of the margin during the folding operation. p

37. A machine for folding the margin at the corner of a cover over the rounded corhaving, in combination, a folder movable over the backing to fold the margin and a cooperating member adapted to facilitate the formation of evenly spaced plaits in the margin, said member being located in the path of movement of the folder, and yielding means for opposing movement of the member in a direction away from the folder whereby the margin is gripped frictionally be tween the operative faces of the member and the folder and drawn about the rounded cor ner of the backing. c

39. A machine for folding the margin of a cover over' the rounded corner offla backing having, in combination,'a reciprocating folder movable over the body portio'n of the work, anda member adapted to cooperate with the folder to facilitate the-formation of evenly spaced plaits, said member bein located inthepath of movement of the folder and having a portion extending above the folder.

40. A machine for folding a cover over the rounded corner of a backing having, in combination, a folder movable 451. A machine for folding the margin of a cover-over the rounded corner of a back-P ing having, in combination, a'support for the corner portion of the work, means for imparting a bend to the margin, a folder, a member adapted to cooperate with the folder to facilitate the formation of evenly spaced plaits in the margin, said member being normally located in the path of movement of the folder, and means for causingthe' folder first to press a portion of the margin against the member and then to move the margin progressively beneath the memberan'd lay it down upon the body portion 'of the work.

42. A m chine for folding-the margin of a cove'rover'the rounded corner of a backing the margin; of 4 g um having, in combination, a support for the corner of the work, means for bending up the margin, a tool having a plurality of ribs on its operative face, and means for folding the margin over the body portion of the work and at the same time ,dra-gging'the margin over the face of the tool. p

43. p A machine for folding the margin at the corner ofthe cover of a book case over the round corner of a board thereof having, in combination, a support for the work, a folder movable over the board to fold the margin of the cover, a member adapted to cooperate with the folder to facilitate the formation of evenly spaced plaits in the margin, yielding means for holding the member normally in the path of movement of the folder, and means including the yielding means for permitting the member to rise during the folding operation so that the folder may move be-' neath it. 7 r

44:. A machine for folding the margin at the corner of the cover of a book case over the round corner of aboard thereof having, in combination, a folder, a member located in the path ofmovement of the folder and adapted to cooperate with the folder in the formation of plaits in the margin, and means for causing the folder and, the member to move at the same time and, while moving, to grip and bend over the margin.

45. A machine for folding the margin at the corner of the'cover of a book case over the round corner of a board thereof having, in

combination, an edge guide having two faces arranged to include between them an angle substantially the same as that which is to be included between the two folded edges of the cover adjacent to the round corner, a folder having two faces which include between them a smaller angle, and means for reciprocating the folder and for holding it from lateral oscillation.

46. A machine for folding the margin at the corner of the cover of a book case over the rounded corner of a board thereof having, in combination, a support for the corner portion of the work, a folder, means for moving the folder over the board and for preventing the folder from oscillation during said movement, a member adapted to cooperate with the folder in the formation of plaits, said member being located in the path of movement of the folder and mounted for movement during the folding operation, and means for pressing the fold.

47. A machine for folding the margin at the corner of the cover of a book case over the rounded corner of a board thereof having, in combination, a support for the corner portion of the work, a folder, means for moving the folder over the board and for preventing the folder from oscillation during said movement, a member adapted to cooperate with the folder in the formation of plaits, said member being located in the path of movement of the folder and mounted for movement during the folding operation, means for causing the margin to be held against the folder by the memher and for causing the member to move with the folder, and means for pressing the fold.

48. A machine for folding the margin at the corner of the cover of a book case over the rounded corner of a board thereof having, incombination, a support for the corner portion of the work, a folder movable in a straight path over the support, and a member adapted to cooperate with the folder in the formation of plaits, said member being located in the path of movement of the folder and movable with the folder during the entire folding oporation.

4 9. A machine for folding the margin at the corner of the cover of a book case over the rounded corner of a board thereof having, in combination, a work support, a movable folder, a yieldingly mounted member adapted to cooperate with the folder in the formation of plaits, said member being located in the path of movement of the folder, and means for causing the folder to press the margin against the member and to move themember during the folding operation.

50 A m achine for folding the margin at the corner. of the cover of a book case over the rounded cornerof a board thereof having, in combination, a work support, a movable folder, a yieldingly mounted pivoted 'member adapted to cooperate with the folder in the formation of plaits, said member being located in the path of movement of the folder, and means for causing the folder to press the margin against the member and to swing the member about its pivot during the folding operation.

51. A machine for folding the margin at the corner of the cover of a book case over the round corner of a board thereof having, in combination, a substantially flat Work support, a folder reciprocable in a straight path substantially parallel to the surface of the support, a member adapted to cooperate with thefolder in the formation of evenly spaced plaits in the margin, said member being normally held above the support, means for bringing the member down upon the work and for bending up the margin into a position between the member and the folder, and means for causing the folder to force the margin against the member so as to grip it frictionally and to fold the margin over the board.

In testimony whereof I have signed my name to this specification.

PERLEY R. GLASS. 

